Talk:Zeta Herculis
binary/trinary & planetary orbits I've renamed this from Zeta Herculis B to just Zeta Herculis as it's a binary, possibly trinary system. No reason to have them all split into separate pages when they are so intimately connected. I don't know enough about Wallenstein to know if we are just designating Herc B as Wallenstein System or both/all three stars as the system. Additionally, Herc A and B are fairly close (15 AU). So close they would sit between Uranus and the sun (19 AU). Are the planets orbiting just Herc B or around the center of solar mass? Nether was made clear from the pages contents, but implied the former so that's how I left it. I'm concerned that planetary formation would be greatly different from the information given due to the binary/trinary nature of the system, but it's late and I'd need to research the situation further. Anyway, this deserves discussion as it's an intriguing situation and there is much that could be added to this page. Silvak (talk) 06:09, April 19, 2015 (UTC) Hi Silvak; Renaming to Zeta Herculis as a system is actually a good idea as we're covering the entire system on this page. And I do favor treating the system's stars as one for this purpose, as they are in close rotation around a common center. Because Zeta Herculis' stars are so close, the planets orbit both stars (circumbinary) in a retrograde (clockwise) orbit in what is termed a P-type planetary orbit. And you are correct in your concern about this system. A planet won't form around one star (S-type planetary orbit) in a close orbit multi-star system as it would be torn apart nearing the star's center of rotation. S-type planetary orbits are possible, but the stars have to be much further apart. From what I've been able to find, physics mean that only retrograde orbits are stable. If you would like to see orbit simulations this site has several. This is a simulation of 5 planets is P-type planetary orbit. Hmm, perhaps a wiki page on circumbinary planets? What do you think? Regards, Dusty Hicksdustin (talk) 11:25, April 19, 2015 (UTC) That is some great information Dusty! And we should definitely have this information on GalNet. Silvak (talk) 14:53, April 19, 2015 (UTC) Ok, I'll start working on that page. Interestingly enough, the more planets in the system, the stranger the orbits get. BTW, The failed star that makes Nilfeheim's orbit "weird" means Solken System could be considered to be a binary system with the planets in a S-type orbit. (the brown dwarf likely would not be within 12-15 AU of Solken to allow this, but is likely further away, unless the other planets are within 3 AU of Solken). Dusty Hicksdustin (talk) 20:57, April 19, 2015 (UTC) Fascinating! I love both the pictures. I didn't know that Solken had a brown dwarf in/near it.....and the wiki page doesn't seem to mention it either. Silvak (talk) 21:52, April 19, 2015 (UTC) Right, that's in Vanessa's latest rewrite of Eric Olafson, Neo-Viking. It's what actually causes Nilfeheim's elongated orbit, creating the Shortsummer/Longwinter phenomenon. Here's the quote (italics mine): "Nilfeheim is the 2nd planet in the Solken System, a Type 4D Garden world. The planet is on an elliptic orbit around its sun. A second failed sun , a supermassive Gas giant is the cause for this unusual orbit and the reason for long cold winters that can last up to seven standard (Terran) years." And of course another name for a failed sun is "Brown Dwarf" I'll edit Solken System's page here shortly (I forgot about it after the rewrite, and hadn't looked at that page in quite a while) :-) Dusty Hicksdustin (talk) 22:21, April 19, 2015 (UTC) Also, if you'd like to see more simulations (in motion!) go to Orbital Research. They cover: HTML5, Video & Java simulations, Galaxies, Exoplanets (in binary star systems), Triple stars, Solar systems and have links to other sites Dusty Hicksdustin (talk) 22:58, April 19, 2015 (UTC)